Origin

A slough is a swamp (slōh in Old English), and a slough of despond a condition of despondency, hopelessness, and gloom. The phrase comes from John Bunyan's The Pilgrim's Progress ( 1678), where it is the name of a deep boggy place between the City of Destruction and the gate at the beginning of Christian's journey. Slump (late 17th century) originally meant to fall in a bog and probably came from the sound that would be made. The economic sense is late 19th century. Slough in southern England also takes its name from Old English slōh, not the most appealing of origins. To add to the unglamorous town's image problems, the English poet John Betjeman wrote of it in 1937: ‘Come, friendly bombs, and fall on Slough! / It isn't fit for humans now.’ The slough meaning the skin shed by a snake is Middle English and originally meant ‘skin’ in English. It may be related to Low German sluwe ‘husk, peel’.